global: private xpub support part 2

website_next/wallets/add/inference.js

@@ -0,0 +1,49 @@
+import { fetchWalletAddresses } from "../lookup/index.js";
+import {
+  generateAddressesFromKey,
+  isOutputDescriptor,
+} from "../derive/index.js";
+import { parseOutputDescriptor } from "../derive/descriptor.js";
+import { addressScripts } from "../derive/script.js";
+
+const RECEIVE_PATH = /** @type {const} */ ([0]);
+
+/**
+ * @typedef {import("../derive/address.js").AddressScript} AddressScript
+ * @typedef {import("../scan/branch.js").AddressClient} AddressClient
+ * @typedef {import("../lookup/index.js").WalletAddress} WalletAddress
+ */
+
+/**
+ * @param {WalletAddress} address
+ */
+function hasHistory(address) {
+  return address.received > 0 || address.sent > 0 || address.txCount > 0;
+}
+
+/**
+ * @param {AddressClient} client
+ * @param {string} source
+ * @returns {Promise<AddressScript>}
+ */
+export async function inferAddressScript(client, source) {
+  if (isOutputDescriptor(source)) {
+    return parseOutputDescriptor(source).script;
+  }
+
+  for (const { id } of addressScripts) {
+    const generated = await generateAddressesFromKey(source, {
+      start: 0,
+      count: 1,
+      script: id,
+      path: RECEIVE_PATH,
+    });
+    const [address] = await fetchWalletAddresses(client, generated);
+
+    if (address && hasHistory(address)) {
+      return id;
+    }
+  }
+
+  return addressScripts[0].id;
+}